Mathematics · 2021
JEE Main · 27 August 2021, Shift 2 · Q82
Let S ={1,2,3,4,5,6,9}. Then the number of elements in the set T ={ A ⊆ S: A ≠ φ and the sum of all the elements of A is not a multiple of 3} is \ \…
Let $\displaystyle \mathrm{S}=\{1,2,3,4,5,6,9\}$. Then the number of elements in the set $\displaystyle \mathrm{T}=\{\mathrm{A} \subseteq \mathrm{S}: \mathrm{A} \neq \phi$ and the sum of all the elements of A is not a multiple of $\displaystyle 3$} is \_\_\_\_.
Official answer
80
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.